Lionel Bringuier, the French conductor, made his New York debut on Tuesday night. But readers of this newspaper have had a taste of him before. In January 2007, he conducted in Davos, Switzerland. I wrote, “It’s always risky to say that someone, in any field, is can’t miss, but it’s not so risky in this case.” At the time, Maestro Bringuier was 20 years old. He is now a seasoned 21. And he is, indeed, can’t miss. In fact, he has already arrived.

Mr. Bringuier is assistant to Maestro Esa-Pekka Salonen at the Los Angeles Philharmonic. And, in September 2009, Gustavo Dudamel, now 27, will become music director of that orchestra. Obviously, they like ’em young in L.A.

This season, Mr. Bringuier will conduct big orchestras, including the Cleveland Orchestra and our own New York Philharmonic. This week, he conducted the Mostly Mozart Festival Orchestra in Avery Fisher Hall. And he was superb.

On the program were three ultra-familiar works, and three great ones. First was the overture to Mozart’s “Marriage of Figaro.” It was not a race, blessedly. These days, this overture is usually conducted zippy, zippy, zippy. But from Mr. Bringuier, it was graceful and beautiful. In fact, I had forgotten how beautiful this overture is.

Mr. Bringuier was strict in his rhythm, but not at all mechanical. He was interesting in his dynamics, but not showy or obtrusive. Was the overture a tad dull — just a little? Maybe. And the orchestra’s execution was subpar. But the piece was very enjoyable nonetheless.

Then it was concerto time — a Mozart piano concerto, No. 25 in C major, Op. 503. This is one of the great concertos, for anything, by anyone. It has a spiritual nobility. You could almost think of some great benevolent king.

The soloist in it was Garrick Ohlsson, the veteran American pianist. He is a big man who likes big pieces (Liszt, Chopin, Scriabin) — but he also likes Mozart, and Mozart likes him, pretty much. Mr. Ohlsson did some exemplary playing in this concerto. He was lapidary and liquid. He was both tart and sweet. The Andante, at its best, had a quiet grandeur. And the closing Allegretto was the best movement of all. Mr. Ohlsson gave it a manly playfulness.

But there were some problems. First, Mr. Ohlsson’s sound was sometimes tinny, which is not a word often associated with the piano. Was it the soloist or the instrument? Second, Mr. Ohlsson committed some rushing, particularly during the first movement — this was during passagework. Third, Mr. Ohlsson’s playing sometimes suffered from the quality of okayness. What I mean is, this playing was unobjectionable, but lacking a certain sparkle or inspiration.

In any event, Mr. Ohlsson was never incompetent or unreasonable. He is a professional who always delivers for you. And, by the way, he used a cadenza written by his colleague, Alfred Brendel. I found it overly episodic and busy — almost scattered. But it was nice to hear something out of the ordinary.

As for Mr. Bringuier, his conducting in this concerto was extremely mature — a word I use irrespective of age, believe it or not. This conducting was sensible but never boring. There was not a throwaway measure, or a time when you thought, “This is just filler.” Everything mattered. Mr. Bringuier was not the least flashy, as Mr. Dudamel, among others, can be. Instead, he was musical all the way — you could even say pure.

Where he really shone was in Beethoven’s Fourth Symphony, the offering after intermission. Mr. Bringuier is a natural communicator — both to an orchestra and to an audience. His gestures are elegant and fairly big. They are not economical, and they are not excessive. Mr. Bringuier does what it takes, in his own, tasteful, expressive way.

On every page of Beethoven’s Fourth, a musical intelligence was present. Mr. Bringuier is a respecter of the old musical values concerning rhythm, phrasing, dynamics, etc. He is attentive to detail, but conscious of the overall picture. There is no ego in his conducting, and may there never be. (Will people tell him to be more “individual”?) Beethoven was in very good hands.

His second movement, Adagio, was loving but not smothered or smothering. The ensuing minuet was merry but somehow aristocratic — elegant. And its tempos, like the other movements’ tempos, were perfect: Fasts were not too fast; slows were not too slow. And the closing Allegro was simply covered with pleasure.

Woodwinds of the Mostly Mozart Festival Orchestra were excellent — particularly in the Adagio. For instance, the oboe was so inoffensive in its sound, the man may find himself kicked out of the Oboists’ Guild. The horns, I should add, were happily unflubbing.

When it was all over, the crowd cheered like crazy for Mr. Bringuier (who looks about 12, by the way). There would be no encore, however — the “Marriage of Figaro” Overture had already been played.